Seagate firmware difference on 7200.10 causes 20mb/s performance drop?
 

Benchmarks are posted all over the web by people who want to know if the hardware they just bought actually performs within specs. Some owners of the Seagate 7200.10 were disappointed that their disk did not perform as presented in various benchmarks found on the web. So where the AAE disk starts at 75MB/s the AAK disk starts at less than 55MB/s, a 20MB/s difference!

http://www.fluffles.net/articles/seagate-AAK-firmware